xen-netback: use local var in xenvif_tx_check_gop() instead of re-calculating

jbeulich · davem330 · commit 826d82170b53 · 2021-03-01T13:05:08.000-08:00
shinfo already holds the result of skb_shinfo(skb) at this point - no
need to re-invoke the construct even twice.

Signed-off-by: Jan Beulich &lt;jbeulich@suse.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
@@ -557,8 +557,8 @@ static int xenvif_tx_check_gop(struct xenvif_queue *queue,
 	}
 
 	if (skb_has_frag_list(skb) && !first_shinfo) {
-		first_shinfo = skb_shinfo(skb);
-		shinfo = skb_shinfo(skb_shinfo(skb)->frag_list);
+		first_shinfo = shinfo;
+		shinfo = skb_shinfo(shinfo->frag_list);
 		nr_frags = shinfo->nr_frags;
 
 		goto check_frags;

Original file line number	Diff line number	Diff line change
`@@ -557,8 +557,8 @@ static int xenvif_tx_check_gop(struct xenvif_queue *queue,`
`557`	`557`	`}`
`558`	`558`
`559`	`559`	`if (skb_has_frag_list(skb) && !first_shinfo) {`
`560`		`- first_shinfo = skb_shinfo(skb);`
`561`		`- shinfo = skb_shinfo(skb_shinfo(skb)->frag_list);`
	`560`	`+ first_shinfo = shinfo;`
	`561`	`+ shinfo = skb_shinfo(shinfo->frag_list);`
`562`	`562`	`nr_frags = shinfo->nr_frags;`
`563`	`563`
`564`	`564`	`goto check_frags;`